thiosulfuric acid

== English == === Alternative forms === thiosulphuric acid (mainly UK) === Etymology === From thio- +‎ sulfuric acid. === Noun === thiosulfuric acid (uncountable) (inorganic chemistry) An unstable acid, H2S2O3, formally derived from sulfuric acid by the substitution of a sulfur atom in the place of an oxygen one; it is known only in solution or as its salts and esters, the thiosulfates. ==== Translations ====